1089. Duplicate Zeros
class Solution:
def duplicateZeros(self, arr: List[int]) -> None:
"""
Do not return anything, modify arr in-place instead.
"""
i = 0
n = len(arr)
while i < n:
if arr[i] == 0:
arr[::] = arr[:i] + [0] + arr[i:n-1]
i += 2
else:
i += 1